Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
  • A61F2/01—Filters implantable into blood vessels
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
  • A61F2/01—Filters implantable into blood vessels
  • A61F2002/018—Filters implantable into blood vessels made from tubes or sheets of material, e.g. by etching or laser-cutting
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2230/00—Geometry of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof
  • A61F2230/0002—Two-dimensional shapes, e.g. cross-sections
  • A61F2230/0004—Rounded shapes, e.g. with rounded corners
  • A61F2230/0006—Rounded shapes, e.g. with rounded corners circular
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2230/00—Geometry of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof
  • A61F2230/0002—Two-dimensional shapes, e.g. cross-sections
  • A61F2230/0004—Rounded shapes, e.g. with rounded corners
  • A61F2230/0008—Rounded shapes, e.g. with rounded corners elliptical or oval
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2230/00—Geometry of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof
  • A61F2230/0063—Three-dimensional shapes
  • A61F2230/0073—Quadric-shaped
  • A61F2230/008—Quadric-shaped paraboloidal

Definitions

• the present invention relates to apparatus and methods for filtering or removing matter from within a vascular system. More particularly, the present invention provides a low profile self-expanding vascular device useful for capturing emboli or foreign bodies generated during interventional procedures, and for thrombectomy and embolectomy.
• Percutaneous interventional procedures to treat occlusive vascular disease such as angioplasty, atherectomy and stenting, often dislodge material from the vessel walls.
• This dislodged material known as emboli, enters the bloodstream, and may be large enough to occlude smaller downstream vessels, potentially blocking blood flow to tissue.
• emboli enters the bloodstream, and may be large enough to occlude smaller downstream vessels, potentially blocking blood flow to tissue.
• the resulting ischemia poses a serious threat to the health or life of a patient if the blockage occurs in critical tissue, such as the heart, lungs, or brain.
• stents and stent-grafts to treat vascular disease also involves the introduction of foreign objects into the bloodstream, and also may result in the formation of clots or release of emboli.
• Such particulate matter if released into the bloodstream, also may cause infarction or stroke.
• interventional procedures may generate foreign bodies that are left within a patient's bloodstream, thereby endangering the life of the patient.
• Foreign bodies may include, for example, a broken guide wire, pieces of a stent, or pieces of a catheter.
• U.S. Patent No. 5,814,064 to Daniel et al. describes an emboli filter system having a radially expandable mesh filter disposed on the distal end of a guide wire.
• the filter is deployed distal to a region of stenosis, and any interventional devices, such as angioplasty balloons or stent delivery systems, are advanced along the guide wire.
• the filter is designed to capture emboli generated during treatment of the stenosis while permitting blood to flow through the filter.
• Similar filter systems are described in U.S. Patent No. 4,723,549 to Wholey et al . and U.S. Patent No. 5,827,324 to Cassell et al .
• WO 98/39053 describes a filter system comprising an elongated member, a radially expandable hoop and a cone-shaped basket.
• the hoop is affixed to the elongated member, and the cone-shaped basket is attached to the hoop and the elongated member, so that the hoop forms the mouth of the basket.
• the filter system includes a specially configured delivery catheter that retains the mouth of the basket in a radially retracted position during delivery.
• vascular device e.g., for use as a vascular filter, that overcomes such disadvantages and employs few components.
• vascular device that is capable of being contracted to a small delivery profile, thus permitting use of the device in small vessels.
• vascular device that is capable of being contracted to a sufficiently small profile that it may be retrieved using the guide wire lumen of previously known treatment devices, and without the need for specialized delivery catheters.
• vascular device that overcomes disadvantages of previously known vascular filters, thrombectomy/embolectomy and foreign body removal devices, and employs few components.
• a vascular device suitable for use as a vascular filter or thrombectomy/embolectomy device that comprises a blood permeable sac affixed at its perimeter to a support hoop having an articulation region.
• the support hoop is attached to a distal region of an elongated member, such as a guide wire, and supports a proximally- oriented mouth of the sac when the device is deployed in a vessel.
• the device may also comprise a nose cone to facilitate percutaneous introduction, and a delivery sheath having one or more lumens.
• the lumens may further be configured for a rapid exchange mode of introduction along the guide wire.
• the support hoop includes one or more reduced-thickness articulation regions that enable the support hoop to be contracted to very small radii of curvature without the problems of increased stiffness and kinking of previously known devices.
• the articulation region may comprise a gap in the support hoop bridged by the perimeter of the blood permeable sac.
• the support hoop preferably also has a curved profile that prevents the articulation region, when folded, from damaging the wall of the vessel.
• the curved profile permits the device to effectively contact the walls of the vessel and reduce emboli or thrombus removed from the vessel wall from bypassing the sac.
• the articulation region when combined with a support hoop having a curved profile, causes the sides of the support hoop to fold inwards towards one-another when the vascular device is collapsed into a sheath for removal. This, in turn, closes the mouth of the sac and reduces the potential for emboli or thrombus to be released from the vascular device during removal.
• an articulation region permits vascular devices of the present invention to be contracted to very small diameters, thereby enabling the use of delivery catheters having diameters as small as 3 Fr.
• the vascular devices may be retracted within the guide wire lumens of conventional treatment devices, such as angioplasty catheters and stent delivery systems, thereby obviating the need to re-insert a specialized delivery catheter to remove the vascular device.
• a retrieval sheath having a distal region that flares or expands outwardly to receive the emboli-filled sac upon completion of an interventional procedure, and which reduces risk of rupture to the sac, optionally may be provided in accordance with the present invention.
• the vascular device may include a separate guide wire for introducing treatment devices proximal of the deployed vascular device. Additionally, the vascular device may have a second support hoop attached to the distal end of the sac.
• multiple hoops ensure that emboli are retained within the sac and prevent the sac from bunching. Where multiple hoops are rotated, they may be arranged such that they rotate independently of the guide wire, thereby reducing risk that the sac wall will become twisted during advancement. In alternative embodiments, sac bunching is mitigated by tapering the sac and attaching it to one or more support hoops, or to the guide wire.
• Sac porosity may also be specified to ensure passage of blood cells and capture of emboli, as well as to control a pressure drop across the vascular device.
• a delivery sheath is provided that permits a lesion to first be crossed with an unencumbered guide wire prior to passing the vascular device across the lesion.
• several support hoops may be provided at the mouth of a single sac to facilitate opening and closing of the sac.
• a separate thrombectomy element may be provided in addition to the vascular filter.
• the thrombectomy element may be attached to the elongated member proximal of the vascular filter or may comprise a separate catheter.
• the thrombectomy element is similar in construction to the vascular filter and may be retracted independently.
• the thrombectomy element may be any conventional atherectomy device used in conjunction with the vascular filter and may be advanced and retracted either in conjunction or independently of the vascular filter.
• a delivery system in accordance with the present invention configured for use with the vascular devices described herein, is also provided.
• the delivery system integrates the functions of a Touhy Borst, a torquer, and a pusher into a single device, thereby facilitating introduction and retrieval of embodiments of the present invention.
• the torqueing function allows a vascular device to navigate tortuous anatomy. For example, the distal end of a guide wire may be rotated to selectively orient the vascular device in a selected branch of a bifurcated vessel.
• the Touhy-Borst adapter permits liquid to be introduced or withdrawn through the lumen of the vascular device delivery catheter.
• the pusher feature of the delivery system allows deployment and retraction of the vascular device from within the delivery catheter.
• Methods of using embodiments of the present invention are also provided, including use of novel radiopaque features, and use of a previously known balloon catheter to arrest antegrade flow through a vessel until the vascular device of the present invention is deployed.
• FIGS. IA and IB are, respectively, a side- sectional view of a previously known vascular device contracted within a delivery sheath, and an end view of that vascular device deployed in a vessel;
• FIGS. 2A and 2B are, respectively, a perspective view of a vascular device constructed in accordance with the principles of the present invention in a deployed state, and a detailed view of the articulation region of the device of FIG. 2A;
• FIG. 3 is a perspective view of the vascular device of FIGS. 2 in a folded configuration, prior to removal;
• FIG. 4 is a plan view of the vascular device of FIGS. 2;
• FIGS. 5A-5D are side sectional views depicting a method of deploying, using, and retrieving the vascular device of FIGS. 2-4;
• FIG. 6 is a perspective view of an alternative embodiment of a vascular device of the present invention in a deployed state
• FIGS. 7A and 7B are, respectively, a perspective view and a plan view of a further alternative embodiment of the present invention in a deployed state;
• FIGS. 8A-8E are sectional views of a vascular device disposed within alternative embodiments of delivery sheaths of the present invention.
• FIG. 9 is a side view of a previously known balloon catheter
• FIGS. 10A-10D are views illustrating the steps of using the balloon catheter of FIG. 9 with the vascular device of FIGS. 2;
• FIGS. 11A-11C are perspective views of further alternative embodiments of vascular devices constructed in accordance with the principles of the present invention.
• FIG. 12 is a perspective view of an alternative embodiment of the vascular device of the present invention with two support hoops, shown in a deployed state;
• FIG. 13 is a perspective view of an alternative embodiment of the vascular device of FIG. 12 with a smaller distal support hoop;
• FIG. 14 is a perspective view of a still further alternative embodiment of the vascular device of FIG. 12 that allows the vascular device to independently rotate with respect to the guide wire;
• FIG. 15 is a perspective view of an alternative embodiment of the present invention with a tapered blood permeable sac, shown in a deployed state;
• FIG. 16 is a perspective view of a radiopaque support hoop constructed in accordance with one aspect of the present invention.
• FIGS. 17A-17C illustrate another alternative embodiment of the vascular device of the present invention in which the articulation region comprises a gap in the support hoop bridged by the perimeter of the blood permeable sac;
• FIGS. 18A and 18B are side-sectional views depicting an integrated vascular device of the present invention suitable for thrombectomy, disposed, respectively, within a delivery sheath and in a deployed state;
• FIGS. 19A-19E are side-sectional views depicting a method of deploying, using, and retrieving the integrated vascular device of FIGS. 18;
• FIGS. 20A and 20B are side-sectional views depicting an alternative embodiment of the integrated vascular device of FIGS. 18, disposed, respectively, within a delivery sheath and in a deployed state;
• FIGS. 21A and 21B are side sectional views of a delivery system constructed in accordance with the present invention coupled to the vascular device of FIG. 5A, shown, respectively, in a delivery configuration and in a deployed configuration;
• FIGS. 22A-22E are side sectional views depicting a method of deploying, using, and retrieving a vascular device of the present invention in conjunction with a specially configured retrieval sheath;
• FIGS. 23A and 23B are side sectional views depicting a method of using and retrieving the vascular device in conjunction with an alternative embodiment of the specially configured retrieval sheath.
• the vascular filter comprises guide wire 10 having hoop 12 coupled to its end.
• Filter sac 14 is affixed to hoop 12, so that when delivery catheter 16 is retracted proximally and guide wire 10 is held stationary, hoop 12 radially expands to contact the walls of vessel V.
• one difficulty with such vascular filters is that the hoop used to support the filter sac experiences increased stiffness when contracted to small diameters, i.e., due to the sharp directional change at the tip of the hoop, thereby limiting the minimum delivery profile achievable for such instruments.
• this effect may be reduced by decreasing the thickness of the wire employed in hoop 12, at the point at which the wire becomes sufficiently thin to accommodate the bending stresses, the wire is too thin to effectively radially expand and urge the filter sac into engagement with the vessel wall .
• the bending stresses imposed upon the hoop of such previously known devices, if drawn within a delivery catheter, may be sufficiently high to result in the formation of kink 18 at the tip of the hoop.
• This "kinking" effect becomes more severe in sheaths having a small inner diameter.
• Kink 18 in turn may apply relatively high localized pressure and friction against wall 17 of sheath 16, thereby making the vascular filter difficult to deploy.
• the kink may impale wall 17 of delivery sheath 16 and may make it difficult or impossible to deploy the vascular filter, especially in tortuous anatomy.
• kink 18 may deform the pre-formed shape of hoop 12, impairing the ability of the filter to seal against the walls of vessel V. This may in turn lead to the presence of gaps G between the perimeter of the hoop and the vessel wall, depending upon the severity of the kink. Consequently, emboli may pass through the gaps with antegrade flow and significantly reduce the efficacy of the filter. Additionally, kink 18 may be sufficiently sharp to damage or dissect the wall of vessel V when the filter is deployed.
• the vascular device of the present invention solves the above-described disadvantages, providing a vascular device, suitable for use as a vascular filter or thrombectomy/embolectomy device, with a self- expanding support hoop that is sufficiently thick to radially expand and urge a blood permeable sac into engagement with the vessel wall, but which includes an articulation region that overcomes the problems associated with kinking.
• the vascular device of the present invention includes a reduced thickness articulation region and a pre-formed curved profile that avoids the difficulties of previously known systems while providing a high degree of efficacy in capturing emboli or thrombus, and ease of deployment and retrieval. Referring now to FIGS.
• vascular device 20 constructed in accordance with the principles of the present invention, illustratively an embolic filter, comprises guide wire 22, support hoop 24 having articulation region 26, and blood permeable sac 28 affixed to support hoop 24. Sac 28 is coupled to support hoop 24 so that the support hoop 24 forms an opening for the sac. Support hoop 24 preferably is connected to guide wire 22 near distal end 23 of the guide wire. Sac 28 preferably is constructed of a thin, flexible biocompatible material, such as polyethylene, polypropylene, polyurethane, polyester, polyethylene tetraphlalate, nylon or polytetrafluoroethylene, or combinations thereof. The material should be sufficiently thin, such that the sac is non- thrombogenic.
• Sac 28 includes openings or pores 30 that permit blood cells to pass through the sac substantially unhindered, while capturing any larger emboli, thrombus, or foreign bodies that may be released during a procedure, such as angioplasty or stent placement.
• sac 28 has openings or pores 30 in a range of about 20 to 400 microns in diameter, and more preferably, about approximately 80 microns. These pore sizes permit red blood cells (which have a diameter of approximately 5 microns) to easily pass through the sac, while capturing thrombus or emboli.
• Pores 30 are preferably formed by a laser drilling process.
• a thin sheet of the flexible biocompatible material may be thermoformed to create sac 28, for example, by stretching the sheet over a mandrel, by dip forming, or by blow molding. Sac 28 may alternatively be fabricated from an extruded tube of the biocompatible material.
• a flat metal mask, with tiny holes approximately the size of pores 30, may then be placed in front of the sac.
• a laser having a beam diameter equal to or greater than the diameter of the material illuminates the mask. The laser beam passes through the holes in the mask and strikes the material, thereby forming pores 30 in sac 28.
• Laser drilling may also be accomplished with a laser having a beam diameter approximately the size of pores 30, in which case pores 30 may drilled individually.
• Sac 28 may alternatively comprise a woven material, for example, formed from the above- mentioned polymers, having a pore diameter determined as a function of the pattern and tightness of the weave.
• Support hoop 24 comprises a hoop having a circular or rectangular cross-section that is formed of a super-elastic material, such as a nickel-titanium alloy (“nitinol”) .
• nitinol nickel-titanium alloy
• support hoop 24 resumes its pre-formed shape.
• Support hoop 24 preferably comprises nitinol wire, although it may also be formed from a multi-strand nitinol cable, a spring tempered stainless steel, or other super-elastic material .
• support hoop 24 includes one or more reduced-thickness articulation regions 26, and preformed curved regions 34.
• articulation region 26 includes a region having reduced thickness x compared to thickness t of the remainder of support hoop 24.
• Articulation region 26 and curved regions 34 enable support hoop 24 to fold with a predetermined shape when vascular device 20 is collapsed to a contracted state for delivery or retrieval.
• articulation region 26 is depicted as a localized reduction in the thickness of support hoop 24, as may be achieved, for example, using conventional grinding, chemical etching, or electroless polishing processes.
• support hoop 24 may be continuously tapered along its circumference, so that articulation region 26 results from a more gradual reduction in the wall thickness of the support hoop. Tapering support hoop 24 may permit greater flexibility in the vicinity of articulation region 26, thus enabling support hoop 24 to fold more easily at the articulation region. Such tapering of the thickness of the support hoop along a portion of its circumference also may reduce the potential for stress-induced fracture typically associated with abrupt changes in diameter.
• vascular device In a preferred embodiment of vascular device
• vascular device 20 easily fits within a delivery sheath having an inner diameter of 0.033", and, more preferably, may be used with a delivery sheath having an inner diameter as small as 0.026".
• the deployed diameter of support hoop 24 preferably is approximately 7 mm, while guide wire 22 preferably has a diameter of 0.014".
• the distal end of guide wire 22 also may be tipped with a spring section or coil tip, as is per se known.
• Support hoop 24 preferably is constructed of 0.0055" nitinol wire tapered (by a grinding, chemical etching, or electroless polishing process) to 0.0025" at articulation region 26.
• articulation region 26 preferably consists of a length about 0.05" long and having a diameter of 0.0025", coupled on either side to curved regions 34.
• Each of curved regions 34 includes a length of wire that is tapered from a diameter of 0.055" to a diameter of 0.0025" over a length of about 0.025".
• Support hoop 24 also may include radiopaque features, such as gold or platinum bands 33, spaced at intervals around the circumference of support hoop 24, or a coil of radiopaque material wrapped around the support hoop, as described hereinafter with respect to FIG. 16, or a gold plated coating.
• radiopaque features such as gold or platinum bands 33, spaced at intervals around the circumference of support hoop 24, or a coil of radiopaque material wrapped around the support hoop, as described hereinafter with respect to FIG. 16, or a gold plated coating.
• FIG. 3 depicts vascular device 20 of FIG. 2A in a contracted state
• FIG. 4 illustrates a directional change in support hoop 24 preferably caused by the presence of curved regions 34.
• use of articulation region 26 and the curved profile of support hoop 24 introduced by curved regions 34 also cause support hoop 24 to fold in half during retrieval.
• support hoop 24 folds in half, effectively closing the mouth of blood permeable sac 28 and preventing the escape of collected emboli or thrombus.
• vascular device 20 also may permit the use of a smaller or shallower sac than would otherwise be possible, without increasing the risk of material escaping from the device when the sac is collapsed for retrieval.
• Use of a smaller or shallower sac also enables vascular device 20 to be delivered in a smaller delivery sheath, having an inner diameter as small as 0.026" for the preferred embodiment .
• FIGS. 5A-5D methods of using the vascular device of the present invention as a vascular filter are described.
• guide wire 22 and delivery sheath 40 are manipulated into position within vessel V using well-known percutaneous techniques.
• Vascular device 20 of FIG. 2A is disposed in its contracted delivery state within distal end 42 of delivery sheath 40, and delivery sheath 40 is advanced through the vessel using distal end 23 of guide wire 22.
• Articulation region 26 and curved regions 34 of support hoop 24 enable the sides of the support hoop to fold together and become elongated when drawn within delivery sheath 40.
• the size of delivery sheath 40 and guide wire 22 have been exaggerated to illustrate structure. In reality, the diameter of delivery sheath 40 is approximately an order of magnitude smaller than the internal diameter of vessel V.
• delivery sheath 40 is disposed at a desired location within a patient's vessel V, such as a coronary artery or carotid artery, as determined, for example, by the position of radiopaque band 43 under a fluoroscope, guide wire 22 is held stationary while delivery sheath 40 is retracted proximally.
• delivery sheath 40 may be held stationary while guide wire 22 is advanced. In either case, when vascular device 20 is no longer confined within delivery sheath 40, support hoop 24 expands to seal against the walls of vessel V.
• FIG. 5C once vascular device 20 is deployed in vessel V, other interventional instruments, such as angioplasty catheters, atherectomy devices, or stent delivery systems may be advanced along guide wire 22 to position such devices at treatment zones located proximally of vascular device 20.
• interventional instruments such as angioplasty catheters, atherectomy devices, or stent delivery systems
• angioplasty balloon catheter 44 has been advanced along guide wire 22 to a position proximal of vascular device 20 to trap emboli E, i.e., pieces of plaque dislodged from the walls of vessel V by balloon 46.
• guide wire 22 is pulled proximally to cause the sides of support hoop 24 to collapse together to close the mouth of sac 28 (see FIG. 3) . Additional proximal retraction of guide wire 22 causes support hoop 24 and sac 28 to enter at least partially within the guide wire lumen of angioplasty catheter 44. As depicted in FIG. 5D, only a portion of support hoop 24, near articulation region 26, and a distal portion of sac 28 extend out of the guide wire lumen of angioplasty catheter 44. Alternatively, vascular device 20 may be fully retracted within the guide wire lumen. Angioplasty catheter 44 then is withdrawn with vascular device 20 and any trapped emboli E.
• the compliant design of vascular device 20 permits the device to be contracted to its delivery state within the guide wire lumen of conventional previously known interventional devices. Accordingly, unlike previously known vascular devices, which require removal of the interventional device followed by re-insertion of a specially designed catheter to retrieve the vascular device, the system of the present invention reduces the time, effort and trauma of this additional step. Instead, the vascular device may be readily closed and retrieved upon completion of the interventional procedure.
• Vascular device 20 alternatively may be used in performing thrombectomy/embolectomy.
• the vascular device is deployed in a vessel at a location distal to a lesion, in the manner depicted in FIGS. 5A and 5B .
• vascular device 20 may be retracted proximally to scrape along the wall of the vessel, and excise thrombus so that it is captured in sac 28.
• Delivery sheath 44 may then be re-inserted into the vessel along guide wire 22, and vascular device 20 is retracted and removed from the vessel. Additional thrombectomy embodiments are described hereinbelow with respect to FIGS. 18-20.
• sac 28 is porous so that blood cells may pass through while emboli E are captured.
• a ⁇ the sum of the area of all these pores A ⁇ is less than the internal cross- sectional area ⁇ of vessel V, a pressure drop is expected across the vascular device. This may lead to hemolysis and insufficient downstream flow. If A 1 is greater than or equal to A., the pressure drop is expected to decrease. Proper selection of pore diameter (in the range of 20-400 microns) and pore density ensures that A x is greater than or equal to Ag .
• Selection of a larger pore diameter within the provided range may also reduce the pressure drop by decreasing drag as blood passes through sac 28. Drag may further be decreased by providing elliptical pores through the sac that project round relative to bloodflow when sac 28 is deployed. Furthermore, the porosity of sac 28 may be specified such that, if distal pores become occluded with thrombus, emboli, etc., proximal pores remain open to ensure continuous blood flow. It should also be noted that flow through vessel V is substantially unaffected by placement of sac 28 and hoop 24 in the flow path.
• Vascular device 50 comprises guide wire 51 and support hoops 52 and 53 connected to blood permeable sac 54.
• vascular device 50 includes articulation regions 55 and 56 formed at the intersection of opposing curved regions 57 and 58 of support hoops 52 and 53.
• Sac 54 preferably also is connected to guide wire 51 along its entire length, thereby providing more controlled deployment and removal of vascular device 50.
• Support hoop 53 serves to stabilize and deploy the distal portion of sac 54.
• affixing sac 54 to guide wire 51 may provide a more compact arrangement within a delivery sheath, and prevent bunching of the sac material.
• Vascular device 60 shown in the deployed state, comprises guide wire 61 having multi-turn helical support hoop 63 connected at weld point 62. Blood permeable sac 64 is affixed to the distal-most portion of support hoop 63.
• Support hoop 63 includes one or more side turns 65 that terminate in curved regions 66, as described hereinabove. Curved regions 66 in turn are joined together by articulation region 67.
• side turns 65 are coupled to one another and to the distal region of guide wire 61, e.g., by a weld bead, at point 68.
• vascular device 60 may be contracted to small profile delivery state.
• side turns 65 When deployed from a delivery catheter, such as delivery sheath 40 of FIG. 5A, side turns 65 expand into contact with the walls of the vessel proximal to the location at which curved regions 66 contact the vessel wall. Side turns 65 serve to stabilize the support hoop 63 and sac 64 when vascular device 60 is deployed within a blood vessel.
• side turns 64 are expected to assist in orienting the axis of support hoop 63 and sac 64 in alignment with the longitudinal axis of vessel V. Accordingly, support hoop 63 is expected to reduce the risk of tilting of the vascular device within the vessel, and thus enhance the safety and reliability of the device.
• FIGS. 8A-8E several embodiments of a delivery sheath suitable for use with the vascular device of the present invention are described. Each of these embodiments are designed to permit the physician to first pass a guide wire across a lesion before passing the vascular device of the present invention across the lesion. Thus, the risk of generating emboli, during the step of positioning the vascular device of the present invention distal to a lesion, is expected to be reduced.
• vascular device 70 of the present invention comprises guide wire 71, support hoop 72 and blood permeable sac 73 folded in a contracted delivery state within lumen 74 of delivery sheath 75.
• Vascular device 70 is similar in design to vascular device 20 of FIG. 2A, except that device 70 includes nose cone 76 affixed to distal region 77 of guide wire 71.
• Delivery sheath 75 includes hemostatic fitting 78 at its proximal end and guide wire lumen 79.
• vascular device 70 and guide wire 80 are used as follows. First, unencumbered guide wire 80 is advanced through a vessel until distal region 81 of the guide wire crosses a lesion. The proximal end of guide wire 80 then is inserted into the distal end of guide wire lumen 79 of delivery sheath 75 using previously known "over the wire” techniques.
• Delivery sheath 75 then is advanced over guide wire 80, which is held stationary, until nose cone 76 and a distal portion of the delivery sheath cross the lesion.
• guide wire 80 is withdrawn from the vessel and delivery sheath 75 is retracted proximally, thereby deploying vascular device 70 to its deployed state.
• nose cone 76 remains in the vessel, distal to sac 73, during deployment of the vascular device.
• delivery sheath 75 may once again be advanced along guide wire 71 and the support hoop and sac retracted within lumen 74 of delivery sheath 75.
• an interventional device may be advanced over guide wire 71 to perform a medical procedure, and the vascular device may be retrieved within a guide wire lumen of the interventional device, as discussed hereinabove with respect to FIGS. 5.
• Vascular device 90 of FIG. 8B is similar in construction to that of FIG. 8A, and includes guide wire 91, support hoop 92, blood permeable sac 93 and nose cone 94.
• Delivery sheath 95 includes lumen 96 housing device 90, guide wire lumen 97, and hemostatic fitting 98.
• Guide wire lumen 97 opens through skive 99 in lateral wall 100 of delivery sheath 95.
• Guide wire 101 therefore may be used in accordance with well-known "rapid exchange" techniques, wherein the length of unencumbered guide wire 101 may be significantly shorter than in the case of the "over the wire" arrangement depicted in FIG. 8B.
• Operation of delivery sheath 95 and vascular device 90 is similar to that described hereinabove with respect to FIG. 8A, except that the proximal end of unencumbered guide wire 101 is passed through the distal end of lumen 97 and passes out through skive 99.
• delivery sheath 105 includes lumen 106 that opens through the lateral wall via skive 107, and guide wire lumen 108 that opens through the lateral wall via skive 109. Accordingly, as will be apparent to one of ordinary skill, both vascular device 110 and guide wire 112 may be used as described hereinabove with respect to FIG. 8A and further in accordance with "rapid exchange" techniques.
• Vascular device 113 of FIG. 8D is similar in construction to those described hereinabove.
• Delivery sheath 114 includes lumen 115, guide tube 116, and hemostatic fitting 117.
• Lumen 115 houses device 113 during delivery and retrieval.
• Guide tube 116 comprises guide wire lumen 118, which is configured to receive unencumbered guide wire 119. In operation, the proximal end of guide wire 119 is passed through guide wire lumen 118 of guide tube 116.
• guide wire 119 may be used in accordance with "rapid exchange” techniques described with respect to FIG. 8B and with “over the wire” techniques described with respect to FIG. 8A.
• Vascular device 120 of FIG. 8E is also similar to those described hereinabove.
• Delivery sheath 121 includes lumen 122 and hemostatic fitting 123.
• Lumen 122 houses device 120.
• Guide wire 124 is coupled to and terminates at the proximal end of delivery sheath 121.
• distal end 126 of guide wire 125 of vascular device 120 is first to cross the lesion.
• nose cone 127, attached to guide wire 125, and a distal portion of delivery sheath 121 cross the lesion.
• Guide wire 124 and attached delivery sheath 121 are retracted proximally, thereby deploying vascular device 120 to its deployed state.
• Device 120 may then be retrieved within sheath 121 or within an interventional device, as discussed hereinabove.
• Catheter 130 is constructed of materials typically used in catheters, such as polyethylene or polyurethane, and includes compliant balloon 131 disposed in distal region 132.
• Compliant balloon which may be formed of nylon or latex, is inflated using inflation port 133 at proximal end 134 of the catheter.
• Catheter 135 also includes hemostatic port 136 and an interior lumen through which a delivery sheath may be advanced to pass out of an opening in distal end 137.
• FIGS. 10A-10C a method of using catheter 130 of FIG. 9 in conjunction with the vascular device of the present invention is described.
• a vascular device constructed in accordance with the present invention is advanced across a lesion.
• the vascular device illustratively a vascular filter
• the balloon is deflated, thereby permitting antegrade flow to be established.
• flow through the vessel is stopped prior to deployment of the vascular device, few or no emboli are expected to bypass the filter.
• catheter 130 is disposed in vessel V at a location proximal to lesion L, with the vascular device of the present invention disposed in its contracted delivery state in delivery sheath 138.
• balloon 131 is inflated via inflation port 133 to engage the interior wall of vessel V, thereby arresting antegrade flow in the vessel.
• delivery sheath 130 then is advanced across lesion L so that the support hoop and sac of the vascular device will be disposed distal to lesion L when deployed.
• delivery sheath 138 may generate emboli E as it passes across the lesion.
• emboli will not travel distally in the vessel.
• vascular device 140 Once vascular device 140 is deployed, so that support hoop 141 and sac 142 span vessel V, balloon 131 is deflated. This, in turn, causes antegrade flow to become re-established in vessel V, urging emboli E into sac 142. Catheter 130 then may be withdrawn, and additional treatment devices advanced along guide wire 143 of vascular device 140. Removal of vascular device 140 may be by any of the methods described hereinabove with respect to FIG. 5D.
• FIGS. 11A-11C still further alternative embodiments of vascular devices constructed in accordance with the present invention are described.
• Each of the devices of FIGS. 11A-11C which are shown in the deployed state, includes two or more support hoops to support the blood permeable sac.
• Each of those support hoops in turn includes an articulation region that permits the sides of the support hoops to collapse inwards to each other as described hereinabove with respect to FIGS. 3 and 4.
• vascular device 150 illustratively an embolic filter, comprises guide wire 151, support hoops 152 and 153 having articulation regions 154 and 155, respectively, and blood permeable sac 156 affixed to support hoops 152 and 153.
• Sac 156 is coupled to support hoops 152 and 153 so that the support hoops form an opening for the sac.
• Support hoops 152 and 153 preferably are connected to guide wire 151 near its distal end. Sac 156 is also attached to the distal end of guide wire 151 at point 157.
• Sac 156 preferably is constructed of a thin, flexible biocompatible material, as for the embodiments described hereinabove, and includes openings or pores 158 that permit blood cells to pass through the sac substantially unhindered, while capturing any larger material that may be released during a procedure such as angioplasty or stent placement. Pore sizes are selected as described hereinabove with respect to FIG. 2A.
• Support hoops 152 and 153 comprise hoops having circular or rectangular cross-sections that are formed of a super-elastic material, such as a nickel-titanium alloy (“nitinol”) .
• a super-elastic material such as a nickel-titanium alloy (“nitinol”) .
• nitinol nickel-titanium alloy
• Support hoops 152 and 153 During deployment and retrieval of vascular device 150, support hoops 152 and 153 fold in half and collapse to fit within a small diameter delivery sheath. When the delivery sheath is retracted, support hoops 152 and 153 resume their pre-formed shape and deploy the perimeter of sac 156 into contact with the vessel walls.
• Support hoops 152 and 153 preferably comprise a nitinol wire, but also may be formed from a multistrand nitinol cable, or other super-elastic material.
• support hoops 152 and 153 are affixed to guide wire 151 at ring 159 and include reduced-thickness articulation regions 154 and 155, constructed as described hereinabove. More particularly, support hoops 152 and 153 are pre-formed to form structures having curved regions 160 and 161, respectively, so that articulation regions 154 and 155 are disposed in a portion of the support hoop that is approximately concentric with a vessel wall when vascular device 150 is deployed. Articulation regions 154 and 155 and curved regions 160 and 161 thus enable support hoops 152 and 153 to fold with a pre-determined shape when vascular device 150 is collapsed to a contracted state for delivery or retrieval. In a preferred embodiment of vascular device
• vascular device 150 easily fits within a delivery sheath having an inner diameter of 0.033", and more preferably, may be used with a delivery sheath having an inner diameter as small as 0.026".
• the deployed diameter of vascular device 150 preferably is approximately 7 mm.
• vascular device 150 of FIG. 11A employs two support hoops instead of one and provides central location of guide wire 151 and attachment of blood permeable sac 156 to the distal end of the guide wire. These differences may provide more controlled deployment and removal of vascular device 150.
• affixing sac 156 to guide wire 151 may provide a more compact arrangement within a delivery sheath, and prevent bunching of the sac material.
• Vascular device 170 is similar in construction to vascular device 150, except that vascular device 170 employs three support hoops instead of two.
• Device 170 comprises guide wire 151 and support hoops 171, 172 and 173 connected to blood permeable sac 156.
• vascular device 170 includes articulation regions 174, 175 and 176 formed at the intersection of opposing curved regions 178, 179 and 180 of support hoops 171, 172 and 173.
• Support hoops 171, 172 and 173 preferably are connected to the distal end of guide wire 151 at ring 177.
• Sac 156 preferably also is connected to guide wire 151 at point 157.
• Vascular device 170 is expected to provide similar advantages to those contemplated for vascular device 150.
• Vascular device 190 is similar in construction to vascular devices 150 and 170, except that vascular device 190 employs four articulated support hoops.
• Device 190 comprises guide wire 151 and support hoops 191, 192, 193 and 194 connected to blood permeable sac 156, with articulation regions 195, 196, 197 and 198 formed at the intersection of opposing curved regions 200, 201, 202 and 203 of the respective support hoops 191-194.
• Support hoops 191-194 are preferably connected to the distal end of guide wire 151 at ring 199.
• vascular device 250 illustratively an embolic filter, comprises guide wire 252, support hoops 253 and 254 having articulation regions 255 and 256, respectively, and blood permeable sac 258 affixed to support hoops 253 and 254.
• Sac 258 is coupled to support hoop 253 at its proximal end so that the support hoop forms an opening for the sac.
• Sac 258 is coupled to support hoop 254 at its distal end to prevent emboli from spilling from sac 258 during retrieval.
• Support hoops 253 and 254 preferably are connected to guide wire 252 near distal end 259 of the guide wire.
• Sac 258 has openings or pores 260 that permit red blood cells to easily pass through the sac.
• support hoops 253 and 254 expand and collapse as discussed hereinabove with respect to support hoop 24 of FIGS. 2.
• Support hoops 253 and 254 are attached to guide wire 252 at attachment points 261 and 262, respectively, and further comprise curved regions 263 and 264, respectively.
• Support hoops 253 and 254 may include radiopaque features, such as gold or platinum bands 265, spaced at intervals around the circumference of the hoops. Applicant expects that vascular device 250 may further reduce the risk that captured emboli could spill during retrieval, and also may provide a better seal against the artery.
• Vascular device 270 comprises guide wire 272 on which proximal support hoop 273 and distal support hoop 274 are disposed.
• the proximal and distal portions of blood permeable sac 275 are affixed to support hoops 273 and 274, respectively.
• Proximal support hoop 273 is attached to distal end 271 of guide wire 272 at attachment point 276 and includes articulation region 277 and curved regions 278.
• distal support hoop 274 is attached to guide wire 272 at attachment point 279 and includes articulation region 280 and curved regions 281.
• Sac 275 includes blood permeable pores 282.
• Hoops 273 and 274 may include radiopaque features, such as gold or platinum bands 283, spaced at intervals around the circumference of the hoops.
• Proximal support hoop 273 is significantly larger in circumference than distal hoop 274. Proximal hoop 273 seals against the artery walls and defines the diameter of the mouth of sac 275. Smaller distal hoop 274 prevents emboli from spilling from sac 275 when retrieving device 270. It also allows the diameter of sac 275 to decrease along its length. This taper in sac 275 is expected to reduce the risk that sac 275 will bunch when the sac is retrieved. Sac 275 may further by attached to guide wire 272.
• FIG. 14 discloses a vascular device in accordance with the present invention that overcomes problems associated with twisting of the guide wire during deployment.
• Vascular device 290 comprises guide wire 292 with distal end 293, and support hoops 294 and 295.
• Support hoops 294 and 295 further comprise articulation regions 296 and 297, respectively, and curved regions 298 and 299, respectively.
• the proximal and distal portions of blood permeable sac 300 are attached to support hoops 294 and 295, respectively.
• Sac 300 includes pores 301.
• Support hoops 294 and 295 are attached to sheath 302 at attachment points 303 and 304, respectively.
• Sheath 302 preferably comprises a flexible, 0.001" thick tube made of a biocompatible material, such as polyamide or polytetraethylene .
• Guide wire 292 passes through the lumen of sheath 302.
• Sheath 302 is able to rotate with respect to guide wire 292 but is translationally restrained by stops 305 and 306, for example, solder beads. By attaching support hoops 294 and 295 to sheath 302, rotational problems are mitigated. Sheath 302 only transmits translational motion of guide wire 292 to support hoops 294 and 295. Thus, twisting moments applied to wire 292 will not affect the performance of vascular device 290. Sac 300 may also be attached to sheath 302.
• Vascular device 310 comprises guide wire 312 on which support hoop 313 is disposed.
• Tapered blood permeable sac 314 is affixed to support hoop 313.
• Hoop 313 is attached to distal end 311 of guide wire 312 at attachment point 315 and includes articulation region 316 and curved regions 317.
• Tapered sac 314 includes blood permeable pores 318.
• Hoop 313 may include radiopaque features, such as gold or platinum bands 319, spaced at intervals around the circumference of the hoop.
• the diameter of tapered sac 314 decreases along its length to reduce the risk of bunching when the sac is retrieved. Tapering also reduces the amount of material that must fit within the lumen of a delivery sheath, and thereby allows a delivery sheath of smaller profile to be used. Furthermore, tapering the blood permeable sac reduces the risk that the sac will snag on a stent during retrieval. Because vascular device 310 lacks the distal support hoop of the embodiments of FIGS. 12 and 13, there is a reduced risk of problems associated with twisting. In a preferred embodiment, the diameter at the distal end of tapered sac 314 is less than the internal diameter of the retrieval sheath with which the apparatus is used. Tapered sac 314 may optionally be attached to guide wire 312, for example, to further mitigate bunching.
• Support hoop 320 illustratively shown in the deployed state, comprises articulation region 321, curved regions 322, attachment point 323, and wound radiopaque wire 324.
• wire 324 is platinum and is either round or a strip approximately 0.001" in diameter. Wire 324 is wrapped around hoop 320 all along its circumference.
• Radiopaque wire 324 may be used in conjunction with any of the vascular devices discussed herein. Radiopaque wire 324 may further be used with a wide variety of other vascular filter devices, as are known in the art.
• vascular device 330 comprises guide wire 332 with distal region 333, wishbone support hoop 335, and blood permeable sac 336.
• Wishbone hoop 335 comprises spines 337 and 338 separated by a gap that serves as articulation region 339.
• Articulation region 339 is shown in greater detail in FIG. 17B, which corresponds to the area circled in FIG. 17A taken along section line B—B.
• Blood permeable sac 336 is wrapped around and attached to itself all along its perimeter, creating hem bond 340 and lumen 341. Sac 336 includes pores 347.
• Lumen 341 is configured to receive spines 337 and 338 and bridge the gap between them.
• FIG. 17C is a sectional view taken along line C--C of FIG. 17A, showing hem bond 340 and lumen 341 with spine 338 passing there through.
• wishbone support hoop 335 is attached to sheath 343 at attachment point 344.
• Sheath 343 is similar to sheath 302 of the embodiment of FIG. 14, and preferably comprises a flexible, 0.001" thick tube made of a biocompatible material, such as polyamide or polytetraethylene.
• Distal end 333 of guide wire 332 passes through the lumen of sheath 343.
• Sheath 343 may rotate with respect to guide wire 332 but is translationally restrained by stops 345 and 346, for example, solder beads. Sheath 343 mitigates rotational problems by only transmitting translational motion of guide wire 332 to wishbone hoop 335. Twisting moments applied to wire 332 do not affect the performance of vascular device 330.
• the wishbone design of support hoop 335 advantageously enables a wider variety of materials to be used to fabricate the support hoop.
• Articulation region 339 allows vascular device 330 to deploy and contract in a manner similar to that described above for alternative embodiments. Deployment and retraction of wishbone hoop 335 induces minimal deformation of spines 337 and 338, thereby permitting use of materials such as spring steel.
• the support hoop of the embodiment of FIGS. 17A-17C may advantageously be incorporated in any of the foregoing embodiments .
• the integrated device comprises a thrombectomy element and a vascular filter.
• the thrombectomy element is similar in construction to vascular filter 20 described above and is connected to the guide wire proximal of the vascular filter.
• the thrombectomy element may be disposed on a separate catheter. The thrombectomy element may be retracted independently of the vascular filter.
• integrated vascular device 350 comprises guide wire 351, thrombectomy element 352 including support hoop 353 and blood permeable sac 354, and vascular filter element 355 including support hoop 356 and blood permeable sac 357.
• Filter hoop 356 is attached to guide wire 351 while thrombectomy hoop 353 is attached to ring 358.
• Ring 358 is attached to pull wire 359 and has a bore through which guide wire 351 passes. Ring 358 therefore acts as a linear bearing and allows thrombectomy hoop 353 to be moved by pull wire 359 independently of guide wire 351.
• thrombectomy element 352 may omit sac
• FIG. 18A support hoops 353 and 356 and blood permeable sacs 354 and 356 are contracted to a delivery state within lumen 360 of delivery sheath 361.
• Delivery sheath 361 includes nose cone 362 affixed to distal region 363 of guide wire 351.
• integrated vascular device 350 is shown deployed in a vessel. As illustrated in FIG. 18B, vascular filter
• thrombectomy element 352 engages the vessel wall proximal of vascular filter 355.
• proximal movement of thrombectomy device 352 scrapes thrombus from the wall of the vessel when pull wire 359 pulls ring 358 and support hoop 353 proximally.
• FIGS. 19A-19E an illustrative method of using the integrated vascular device of the present invention for thrombectomy is described.
• guide wire 351 is manipulated into position proximal to thrombus T within vessel V using well-known percutaneous techniques.
• Vascular device 350 of FIGS. 18A and 18B is disposed in its contracted delivery state within the distal end of delivery sheath 361 and the delivery sheath is advanced through the vessel using distal end 363 of guide wire 351.
• the sides of support hoops 353 and 356 are folded together and become elongated when drawn within delivery sheath 361, as described with respect to vascular device 20 of FIGS. 2-4.
• FIG. 19A guide wire 351 is manipulated into position proximal to thrombus T within vessel V using well-known percutaneous techniques.
• Vascular device 350 of FIGS. 18A and 18B is disposed in its contracted delivery state within the distal end of delivery sheath 361 and the delivery sheath is advanced through the vessel using dis
• thrombus T a patient's vessel V, such as a coronary artery or carotid artery, based on the position of, for example, radiopaque bands under a fluoroscope
• integrated vascular device 350 is advanced through thrombus T.
• Distal end 363 of guide wire 351 is advanced through the lesion, then nose cone 362 gradually increases the diameter of the void within thrombus T so that the remainder of delivery sheath 361 can be advanced far enough that thrombectomy element 352 (still within delivery sheath 361) is located distal to thrombus T.
• guide wire 351 With integrated vascular device 350 in position, guide wire 351 is held stationary while delivery sheath 361 is retracted proximally, as seen in FIG. 19C. Alternatively, delivery sheath 361 may be held stationary while guide wire 351 is advanced. In either case, when vascular device 350 is no longer confined within delivery sheath 361, support hoops 353 and 356 expand to seal against the walls of the vessel V and deploy blood permeable sacs 354 and 357, respectively. Blood continues to flow through vessel V in direction A, impeded only by thrombus T.
• thrombus T is removed in the following manner.
• Vascular filter support hoop 353 is rigidly attached to guide wire 351, while thrombectomy support hoop 353 is attached to pull wire 359 via ring 358.
• Thrombectomy element 352 then is retracted proximally to scrape along the wall of the vessel V by motion at the proximal end of pull wire 359.
• Thrombus T located proximal to thrombectomy element 352, is excised so that it is captured in blood permeable sac 354 during the retraction.
• thrombus T has been captured within sac 354, pull wire 359 is pulled proximally to cause the sides of thrombectomy support hoop 353 to collapse together to close the mouth of sac 354 (see FIG. 3) . Additional proximal retraction of pull wire 359 causes support hoop 353 and sac 354 to enter within lumen 360 of delivery sheath 361, restoring normal blood flow to vessel V. Meanwhile, vascular filter 355 is in a position distal to thrombectomy element 352 to trap emboli E, i.e., pieces of plaque dislodged from either thrombus T or the walls of vessel V by thrombectomy element 352.
• emboli E i.e., pieces of plaque dislodged from either thrombus T or the walls of vessel V by thrombectomy element 352.
• filter hoop 356 and sac 357 are retracted into delivery sheath 361 by motion at the proximal end of guide wire 351, in a manner similar to the retraction of hoop 353 and sac 354.
• guide wire 351 has been fully retracted, and nose cone 362 at the distal end 363 of guide wire 351 is again in contact with delivery sheath 361, the delivery sheath is withdrawn with integrated vascular device 350, the trapped thrombus T, and any trapped emboli E.
• the compliant design of integrated vascular device 350 permits the device to be contracted to its delivery state within the guide wire lumen of conventional previously known interventional devices, thereby reducing time, effort, and trauma.
• the vascular device may be readily closed and retrieved upon completion of the interventional procedure .
• Integrated vascular device 370 comprises guide wire 371, thrombectomy element 372, and vascular filter 373 having support hoop 374 and blood permeable sac 375.
• Filter hoop 374 is attached to guide wire 371, while thrombectomy element 372 is disposed to slide along guide wire 371.
• thrombectomy element 372 may be disposed on a separate catheter element that extends either through lumen 377 of delivery sheath 378 or is separately disposed proximal to vascular filter 373.
• FIG. 20A shows thrombectomy element 372 and vascular filter 373 contracted in a delivery state within lumen 377 of delivery sheath 378. Delivery sheath 378 includes nose cone 379 affixed to distal region 380 of guide wire 371.
• integrated vascular device 370 is shown in the deployed state.
• Thrombectomy element 372 may comprise any of a family of known thrombectomy, atherectomy, or, alternatively, drug delivery devices suitable for use in conjunction with vascular filter 373.
• Thrombectomy element 372 may, for example, comprise any of: a rotary ablation device, such as described in U.S. Patent Nos. 4,867,156 to Stack et al . , 4,990,134 to Auth, and 5,314,407 to Auth et al . ; an atherectomy technology, such as described in U.S. Patent Nos. 5,181,920 to Mueller et al., and 5,074,841 to Ademovic et al . ; or a balloon embolectomy technology, such as described in U.S.
• Thrombectomy element 372 may alternatively comprise a wire loop or ring, such as described for the embodiment of FIGS. 18A and 18B, a laser ablation device, a chemical flushing system, etc.
• FIGS. 21A and 21B a delivery system configured for use with embodiments of the present invention is described.
• the delivery system facilitates deployment and retrieval of the embodiments by integrating the functions of a torquer, a Touhy Borst adapter, and a pusher into a single device.
• the delivery system is illustratively used in conjunction with vascular device 20 of FIGS. 2-5.
• vascular device 20 is in the retracted delivery configuration
• FIG. 21B vascular device 20 is in the expanded deployed configuration.
• Delivery system 450 comprises proximal screw cap 452, collet 456, handle 460, rod 464, central screw cap 468, lumen flushing section 472, distal hub 479, and nose piece 486.
• Proximal screw cap 452 includes bore 453 with female screw thread 454 and guide wire lumen 455. Bore 453 extends proximally from the distal face of cap 452. Guide wire lumen 455 extends from the proximal end of bore 453 to the proximal end of cap 452.
• Handle 460 comprises proximal male screw thread 461 configured to engage female screw thread 454 of cap 452, and lumen 462 configured to receive collet 456 in its proximal end and rod 464 in its distal end.
• Lumen 462 has a reduced diameter at the distal end of handle 460 that captures a step on the proximal end of rod 464.
• rod 464 may translate and rotate within, but may not be removed from, lumen 462.
• Guide wire 422 freely passes through collet 456 when screw cap 452 is not securely fastened to handle 460.
• cap 452 When cap 452 is securely fastened to handle 460, it causes collet 456 to elastically deform, decreasing the diameter of the lumen extending through the collet, and frictionally locking guide wire 422 into rigid attachment with collet 456. Guide wire 422 is thereby rigidly connected to handle 460.
• Rod 464 further comprises guide wire lumen 465 extending therethrough.
• Rod 464 has its distal end rigidly and permanently affixed to central screw cap 468.
• Cap 468 comprises female screw thread 469 and lumen 470.
• Lumen 470 includes a proximal reduced- diameter step that captures rod 464 within the proximal end of cap 468, and a distal portion that receives lumen flushing or fluid port section 472.
• Section 472 comprises male screw thread 473, side port 474, bore 475, guide wire lumen 476, and fluid lumen 477.
• Male screw thread 473 is configured to engage female thread 469 of cap 468.
• Section 472 includes a flange disposed just distal of thread 473 that is captured within lumen 470 of cap 468. Thus, cap 468 may be tightened onto and loosened from, but not removed from, section 472.
• Rod 464 is received within bore 475 of section 472.
• Guide wire 22 passes between bore 475 and fluid lumen 477 within guide wire lumen 476.
• Fluid lumen 477 connects side port 474 to the guide wire lumen of delivery sheath 40.
• 0-rings 478 provide a fluid seal at the distal end of lumen 477.
• Distal hub 479 connects section 472 to nose piece 486.
• Hub 479 comprises bore 483, female screw thread 484, and annulus 485 containing tapered projection 481.
• Bore 483 includes flange 482 that rotatably receives section 472 in its proximal end.
• Nose piece 486 comprises male screw thread 487, tapered bore 488, and delivery sheath lumen 489.
• Male screw thread 487 is configured to engage female thread 484 in annulus 485 of hub 479.
• Tapered bore 488 allows tapered projection 481 of hub 479 to extend within nose piece 486 and permit delivery sheath 40 from delivery sheath lumen 489 to extend therethrough.
• O-rings 478 are disposed between the hub 479 and nose piece 486 and between hub 479 and section 472.
• Delivery system 450 advantageously may be implemented in a variety of ways.
• the delivery system may be offered with a delivery catheter or sheath pre-attached.
• proximal screw cap 452 is loosened, and the proximal end of guide wire 22 may be passed through the delivery catheter or sheath, and delivery system 450, until vascular device 20 is in its retracted state within the delivery catheter or sheath. Insertion of the vascular device into the patient may then proceed.
• delivery system 450 may be commercially supplied in the configuration shown in FIG. 5A, i.e., pre-loaded with a delivery catheter or sheath, such as sheath 40, already attached and a vascular device, such as vascular device 20, retracted therein.
• delivery system 450 may be offered without either a delivery sheath or vascular device attached, or the delivery catheter or sheath may be an interventional instrument, such as an angioplasty, atherectomy, or stent delivery catheter.
• FIGS. 5A-5D in conjunction with FIGS. 21A and 21B, a method of using the delivery system of the present invention in conjunction with a vascular filter is described.
• delivery sheath 40 With vascular device 20 contracted within distal end 42 of delivery sheath 40 (FIGS. 5A and 21A) , delivery sheath 40 is attached to delivery system 450 by loosening proximal screw cap 452 and extending the proximal end of guide wire 22 through delivery system 450, with handle 460 in its proximal- most position (FIG. 21A) . Screw cap 452 is then tightened to cause collet 456 to engage guide wire 22 to handle 460.
• Delivery sheath 40 then is advanced through a patient's vasculature using well-known percutaneous techniques using distal end 23 of guide wire 22. If a vessel bifurcation is to be crossed during advancement, handle 460 may be rotated to divert the distal end of sheath 40 into the desired branch of the bifurcation. The rotational moment or torque applied to handle 460 is transmitted to guide wire 22 (when screw cap 452 is tightened) , which causes distal end 23 to rotate and facilitates positioning of vascular device 20 in the proper side of the bifurcation. As shown in FIG.
• delivery sheath 40 is disposed at a desired location within a patient's vessel V, such as a coronary or carotid artery, as determined, for example, by the position of radiopaque band 43 under a fluoroscope.
• a patient's vessel V such as a coronary or carotid artery
• vascular device 20 is held stationary while section 472 and attached delivery sheath 40 are retracted proximally.
• handle 460 may be advanced while section 472 and sheath 40 are held stationary.
• support hoop 24 expands to seal against the walls of the vessel V, as depicted in FIGS. 5B and 21B. Blood continues to flow unimpeded through vessel V in direction A.
• delivery sheath 40 may retrieve vascular device 20 at the conclusion of the procedure, or sheath 40 may be detached from delivery system 450 and removed from the patient. If sheath 40 is detached, guide wire 22 may be removed from delivery system 450 so that other interventional instruments, such as angioplasty catheters, atherectomy devices, or stent delivery systems may be advanced along guide wire 22 to position such devices at treatment zones located proximally of vascular device 20. Guide wire 22 and the interventional catheter then may be passed through and fastened to delivery system 450. For example, as shown in FIG.
• angioplasty balloon catheter 44 may be advanced along guide wire 22 to a position proximal of vascular device 20 so that device 20 may trap emboli E, i.e., pieces of plaque dislodged from the walls of vessel V by balloon 46.
• handle 460 with attached guide wire 22 is pulled proximally to cause the sides of support hoop 24 to collapse together to close the mouth of sac 28 (FIG. 3) .
• Additional proximal retraction of guide wire 22 causes support hoop 24 and sac 28 to enter at least partially within the guide wire lumen of angioplasty catheter 44.
• FIG. 4D only a portion of support hoop 24, near articulation region 26, and a distal portion of sac 28 extend out of the guide wire lumen of angioplasty catheter 44.
• Angioplasty catheter 44 then is withdrawn with vascular device 20 and any trapped emboli E.
• delivery system 450 may be used as part of the thrombectomy/embolectomy procedure described herein above, as well as in a variety of other procedures.
• Embodiments of the present invention may optionally be used in conjunction with a specially configured retrieval sheath. Applicant has determined that bunching of sac 28 in FIG. 5D may occur during retraction into catheter 44, resulting in a retrieval profile that may be difficult to navigate through a patient's vasculature. However, additional proximal retraction of guide wire 22 in an attempt to decrease the profile of sac 28 may generate stress loads sufficient to tear sac 28 and release captured emboli. With reference to FIGS.
• FIG. 22A-22E a specially configured retrieval sheath and methods of use with the vascular device of the present invention are described. As with FIGS. 5, sizes have been exaggerated to illustrate structure.
• guide wire 556 is positioned within vessel V using well-known percutaneous techniques.
• Vascular device 550 is disposed in its contracted delivery state within distal end 554 of delivery sheath 552.
• Retrieval sheath 560 and guide catheter 562 are advanced over delivery sheath 552 to a position located just proximal of distal end 554.
• Retrieval sheath 560 includes collapsible flared end region 564, which is shown in a contracted delivery state within catheter 562 in FIG. 22A. Flared end region 564 has a deployed state, wherein the wall flares outward to form a frustrum of a cone, and a contracted state, wherein the wall is substantially cylindrical. Flared end region 564 preferably includes radiopaque band 566.
• guide wire 556 is held stationary while delivery sheath 552 is retracted proximally.
• delivery sheath 552 may be held stationary while guide wire 556 is advanced.
• support hoop 568 and attached blood permeable sac 570 expands to seal against the walls of the vessel V.
• Sac 570 further comprises radiopaque band 572.
• the curved regions of support hoop orient its articulation region concentrically against the inside wall of the vessel. Blood continues to flow unimpeded through vessel V in direction A.
• guide catheter 562 may be an angioplasty balloon catheter similar to catheter 44 of FIGS. 5C and 5D.
• the interventional procedure generates emboli E proximal of device 550, which travel downstream and are captured in sac 570.
• guide wire 556 upon completion of the interventional procedure, is pulled proximally to cause the sides of support hoop 568 to collapse together to close the mouth of sac 570 (see FIG. 3) . Additional proximal retraction of guide wire 556 causes support hoop 568 and sac 570 to partially enter within distal end 554 of delivery sheath 552. If bunching of the sac is anticipated or suspected, flared sheath 560 may be advanced distally to expand end region 564, which comprises a suitable elastomeric material, such as latex, rubber, or a synthetic variant thereof. As depicted in FIG.
• delivery sheath 552 is retracted proximally while retrieval sheath 560 is held stationary, until radiopaque bands 572 and 566 are concentrically aligned, as determined, for example, with a fluoroscope.
• sheaths 552 and 560 are simultaneously withdrawn proximally while guide catheter 562 is held stationary. This motion causes flared end region 564 to collapse sac 570 to its contracted state. In so doing, flared end region 564 applies a distributed load over the surface of sac 570, thereby decreasing the retrieval profile of sac 570 with reduced risk of rupture of sac 570.
• Vascular device 550 also may be used in performing thrombectomy/embolectomy.
• vascular device 550 is advanced in its retracted state within delivery sheath 552 to a location distal of a lesion. Delivery sheath 552 is withdrawn proximally, and vascular device 550 is deployed. With support hoop 568 in contact with the vessel wall, vascular device 550 may be retracted proximally to scrape along the wall of the vessel and excise thrombus so that it is captured in sac 570. Delivery sheath 552, as well as flared sheath 560 and guide catheter 562, then may be reinserted into the vessel along guide wire 556, and vascular device 550 may be retracted and removed from the vessel in the manner described hereinabove.
• FIGS. 23A and 23B an alternative embodiment of the specially configured retrieval sheath, and methods of use with the vascular device of the present invention, are described. Again, sizes have been exaggerated to illustrate structure.
• guide wire 582 has been positioned within vessel V using well-known percutaneous techniques.
• Vascular device 580 has been expanded to its deployed state after delivery within delivery sheath 584, in the manner discussed hereinabove.
• Support hoop 586 seals against the walls of vessel V, and blood permeable sac 588 is positioned to capture emboli E generated by, for example, an upstream interventional procedure. Blood continues to flow unimpeded through vessel V in direction A.
• Delivery sheath 584 further comprises atraumatic expander 590 disposed on a distal end.
• Retrieval sheath 592 is advanced over delivery sheath 584 to a position located just proximal of expander 590.
• Retrieval sheath 592 includes expandable end region 594, which is shown in a contracted delivery state in FIG. 23A.
• Expandable end region 594 has a deployed state, wherein the wall flares outward to form a frustrum of a cone, and a contracted state, wherein the wall is substantially cylindrical.
• Expander 590 has a larger maximum diameter than end region 594.
• Expandable end region 594 preferably includes radiopaque band 596, while expander 590 preferably includes radiopaque band 598 so that their positions relative to one another may be accurately determined. With respect to FIG.
• guide wire 582 upon completion of the interventional procedure, guide wire 582 is pulled proximally to cause the sides of support hoop 586 to collapse together to close the mouth of sac 588 (see FIG. 3) . Additional proximal retraction of guide wire 582 causes support hoop 586 and sac 588 to partially enter within the distal end of delivery sheath 584. If bunching of the sac is anticipated or suspected, delivery sheath 584 may be retracted proximally while retrieval sheath 592 is held stationery to expand end region 594 of retrieval sheath 592 with expander 590. Delivery sheath 584 is retracted a sufficient distance to protect sac 588 and its embolic contents within end region 594. The distance may be determined by means of radiopaque bands 596 and 598. End region 594 comprises a suitable elastomeric material, such as latex, rubber or a synthetic variant thereof.
• end region 594 in the expanded state allows for retraction of retrieval sheath 592, as well as delivery sheath 584 and vascular device 580 disposed therein, in a manner that mitigates dangerous interaction with the vascular wall. It also allows vascular device 580 to be retrieved in a partially collapsed state that reduces the risk of sac 588 tearing. As with vascular device 550, vascular device 580 may be used in performing thrombectomy/embolectomy.
• the support hoops depicted herein illustratively are shown as oval or heart-shaped in the deployed state, where the shape is exaggerated for the sake of clarity. In preferred embodiments, the support hoops are substantially round when deployed, to ensure contact around the circumference of the support hoop and provide a positive seal against the arterial wall.

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